Combination lock



July 1, 1952 I H. c. BEHRENS ET AL COMBINATION LOCK 3 Sheets-Sheet 1 Filed Sept. 29, 1949 INVENTORS Herder-Z CBeh rens t? fllberi' Lflbbofi By 6 mg 2/ ATTORNEYS y 1, 1952 H. c. BEHRENS ET AL ,774

COMBINATION LOCK Filed Sept. 29, 1949 s Sheets-Sheet 2 4g INVENTORS 118mm aBehr-w w fllber'i Ldqbbozl' y 1952 H. c. BEHRENS ET AL 2,601,774

COMBINATION LOCK Filed Sept. 29, 1949 s Sheets-Sheet 5 Fly/0 I a 24- 50 j] Z INVENTORS 4 Herbert CBe/lrens w fllberi' L. flbbol'i Cay %'T%RNEYS Patented July 1, 1952 COMBINATION LOCK Herbert G. Behrens and Albert L. Abbott, Canton,

Ohio, assignors to Diebold, Incorporated, Canton, Ohio, a corporation of Ohio Application September 29, 1949, Serial No. 118,554

5 Claims.

Our invention or discovery relates to combination locks generally, and particularly to a combination lock such as set forth in U. S. Letters Patent No. 1,956,304 issued to Albert L. Abbott and Charles H. Miller, April 24, 1934, and which includes a case on the rear of the door equipped with the lock, one or more coaxial cylindrical tumblers having equal diameters and being rotatably mounted in the case, a spindle extending from the outside of the door through the door and into the case and the spindle having a dial with a knob mounted on its outer end rotatable within a dial ring on the outer face of the door and the spindle having on its inner end beyond the tumblers a cylindrical cam with an operating notch. Usual pin, lever and circular segment means coact between the cam and the innermost tumbler, and between each tumbler and the next outer tumbler, whereby by manipulation of the dial and setting the combination, the notches of the tumblers are aligned with each other and with the operatin notch of the cam for unlocking the lock.

The lock furthermore includes a reciprocable bolt pivotally connected with one end of an operating lever including an upper arm having a cam follower tongue depending from its outer end, and a stop arm or fence extending from the inner side of the upper arm parallel with the axis of the tumblers. The operating lever is spring pressed towards the tumblers, and when the tumbler notches are aligned with each other and the operating notch of the cam which is located in the aligned position below the cam follower tongue of the upper arm, the fence is permitted to drop into the tumbler notches and the cam follower tongue is permitted to drop into the operating notch of the cam, whereby the bolt may be withdrawn from its extended locking position, and whereby the bolt may be also extended to looking position when the door is again closed and locked by suitable rotations of the dial and spindle. After the bolt is extended into locking position, the spindle is then spun in a reverse direction to scramble the combination by turning the tumblers so that their notche are out of alignment with each other.

Such a look as set forth in said Abbott and Miller U. S. Letters Patent No. 1,956,304, with respect to the parts above described is similar to other usual combination locks. When the bolt is extended and the combination scrambled the fence rests upon the cylindrical peripheries of the tumblers. If such a lock is made in a laboratory to extreme accuracy, and assembled with extreme precision, the lock cannot be manipulated by an unauthorized person so as to detect the combination and effect unlocking. In the usual mass production of the parts of such a lock and the assembly of the same, the extreme accuracy necessary for preventing manipulation cannot be attained. Unless the bottom surface of the fence is exactly parallel with the axis of rotation of the tumblers, and unless the diameters of the tumbler discs are all exactly the same, when the fence rides over the opening formed by one of the tumbler notches, even though its bottom surface ls riding on the peripheries of the remaining tumbler discs, very minute movements of the fence as it rides over the corners of such :a notch can be felt in rotating the dial by. the fingers of an unauthorized person who knows the internal construction of the lock.

In the present instance the internal construction of the lock which enables the unauthorized person to feel the movement of the fence as aforesaid arises from the fact that the operating notch of the cylindrical cam must have rounded upper corners to prevent binding or catching during movements of the operating lever. One side of the notch pulls the tongue to retract the bolt, and the other side of the notch pushes the tongue to extend the bolt and then elevate it. If the notch upper corners are not rounded or tapered, there would be a binding or catching of the tongue in the notch during these actions.

In a perfect lock, in which the cylindrical surfaces of the tumblers are aligned with each other axially and have exactly the same diameters, and in which the cylindrical surface of the cam is exactly coaxial with the cylindrical surfaces of the tumblers, and in which the fence is exactly parallel with the axis of the tumblers and the cam, the fence rides on the cylindrical surfaces of all the tumblers and the lower rounded end. of the tongue rides on the cylindrical surface of the cam. There is no feel transmitted to the knob at any time during manipulation of the look.

In actual practice, however, either the fence may be slightly angled with respect to the axis of the tumblers, or one or more of the tumblers may be slightly larger in diameter than the others or may be eccentric with respect to the others. In any event, the fence in such a lock rides only on one tumbler until it enters the notch of that tumbler.

Moreover, in the usual commercial lock the tongue usually rides on the cylindrical surface of the cam, and when it passes over a corner of the cam notch, the tongue makes a first drop into the By repeating this procedure for each tumbler in succession after the reference point has been detected for the first tumbler, the skillful manipulator is able to detect the entire combination for which the lock is set. Ordinarily, a person skilled in breaking the combination of such a lock can determine the combination by manipulation in the manner described in about twenty minutes.

The objects of the present invention or discovery include the provison of an improved combination lock of the type set forth in the Abbott .and 'Mil'l er U. S. Letters Patent No. 1,956,304, and in which during setting of the combination, the fence is elevated above the peripheries of the tumblers, so that when a tumbler notch corner passes below the fence, it is not in contact with the fence and transmits no feeling to the person manipulating the dial.

Further objects of the present invention or discovery include the provision of such an improved combination lock in which the improvements may be efiected by the addition of or modification of a limited number of parts of the combination lock set forth in said Abbott and Miller U. S. Letters Patent No. "1,956,304, and which is thus adapted for economical manufacture with- 'out the necessity of manufacturing an entirely new set of parts for the improved lock.

The foregoing and other objects are attained by the combination lock, construction, improvements, parts, combinations, and sub-combinations which comprise the present invention or discovery, the nature .of which is set forth in the following general statement, and preferred embodiments of which together with their mode of use are set forth by way of example in the following description, and which are'particularly and distinctly pointed out and set forth in the appended claims forming part hereof.

The nature of the improved combination lock of the present invention or discovery may be stated in general terms as including, in combination with other usual parts of a combination lock such as set forth in said Abbott and Miller U. 3. Letters Patent l-lo.1,956,304=, the provision of a stop pin extending from the upper arm of the operating lever in a direction opposite to the fence, and the provision of a cam actuated spring dog arm having its lower end mounted on a wall of the case, or its equivalent, a spring pressed cam actuated dog arm having its lower end pivotal'ly mounted on a :wa l of the case, and either the spring dog arm or the spring pressed dog arm having its upper end located for movement to and from blocking and supporting position beneath the stop pin .on the operating lever upper arm, in either construction the dog arm having a cam follower portion intermediate its ends,

and the cam on the spindle of the lock having an auxiliary cam notch or cam located for coacting with the cam follower portion of the dog arm to move the upper end of the dog arm in blocking position beneath the stop pin on. the operating lever upper .arm when the operating lever has been elevated to the blocked position. ,After scrambling of the tumblers the operating lever is supported by the dog arm in the elevated position with the fence elevated with clearance above the tumblers, until such time as the lock combinationhas been reset by an authorized person, during which the operation of the auxiliary cam notch in coaction with the cam follower portion of the dog arm serves to displace the upper end of the dog arm from beneath the stop pin, permitting the operating lever cam follower tongue and the fence to drop into the cam notch and the tumbler notches for withdrawing the bolt and subsequently extending the bolt.

By way of example, preferred embodiments of the combination locks ofthe present improvemen-ts and parts thereof are illustrated in the accompanying drawings forming part hereof, in which:

Figure l is a fragmentary oblique perspective view of one embodiment of the improved combination lock looking towards the rear face of the door on which the lock is mounted and with the cover plate of the lock removed, and showing the parts of the lock in their relative positions just before the bolt has been fully extended to the locking position, or just after the bolt has been slightly withdrawn from the lockin Position, with the tumbler Wheels having their notches aligned and with the fence located in the aligned notches and with the cam follower tongue of the operating lever'extending into the operating notch of the :cam, and with the upper end of the dog arm displaced from beneath the stop pin on the operating lever;

Fig. 2 is a view similar to Fig. 1 showing the parts of the lock in their relative positions when the bolt is in its fully extended locking position, the upper end of the dog arm being shown in blocking and supporting position beneath the stoppin, and maintaining the upper arm of the operating lever so that the fence i clear of the peripheries of the tumbler wheels, whereby the tumbler wheels may be scrambled, and Subsequent turning of the tumbler wheels produces no telltale feeling to an unauthorized person endeavoring to manipulate the lock;

Fig.3 isa fragmentary front elevational view looking towards the front face of the door, and illustrating the dial and knob, and dial ring of the lock;

Fig. ,4 is a fragmentary rear elevational view looking towards the rear face of the door on which the lock is mounted, the cover plate of the lock being removed, and the parts of the lock being shown in their relative positions when the bolt is fully withdrawn to the unlocking position;

Fig. .5 is an enlarged detached inner end elevational view showing details of construction of the cam;

Fig. 6 is an enlarged detached side elevational view of the cam with portions broken away and shown in section; I

Fig. 7 is an enlarged detached outer end elevational view of the cam;

Fig. 8 is an enlarged detached side elevational view of the dog arm;

Fig. 9 is an end elevational View thereof, looking in the direction of the arrows 9-9, 'Fig. 8;

Fig. 10 is a fragmentary rear ,elevationalview showing a second embodiment of the improved combination lock hereof, the parts of the lock being shown in their relative positions when the bolt is in the fully extended locking position;

Fig. 11 is a view similar to Fig. 2 showing a third embodiment of the improved combination lock hereof;

Fig. 12 is an end elevational view of the lock of Fig. 11 looking towards the bolt, and with portions broken away and shown in section; and

and the lock may be used for stopping boltwork,

not shown, in a usual manner. The lock 10 includes certain parts :not shown in detail and which are substantially identical with such parts as shown and described in said Abbott and Miller U. S. Letters Patent No. 1,956,304, whereas other parts of the lock construction of said Abbott and Miller U .8. Letters Patent No. 1,956,304 pertinent to the present improvements, are shown and described in detail herein, as well as modified parts of the lock construction of said Abbott and Miller U. S. Letters Patent No. 1,956,304, and parts added thereto for the attainment of the present improvements.

The case I l includes a tube extending from the base wall l of the case, and the base wall is abutted against the inner face 12 of the door l3.

The bore of the tube communicateswith a registering aperture formed in the base or front wall l5of the case, and with an aperture formed in the door 13, and an operating spindle I5 is journalled in the tube and extends through the apertures of the base wall [5 and door 13.

A dial ring I1 is secured upon the front face I8 of the door I3, and the spindle [6 also extends through an aperture formedin the dial ring, and a knob 19 and dial 20 are secured upon the outer end of the operating spindle IS.

The dial may have inscribed thereon 100 equally spaced division lines, each tenth division line of which is numbered successively from to 100'.

A single preferably vertically extending mark or arrow 21 is formed or inscribed on the dial ring above' the knob, and the mark 2| is utilized in conjunction with rotation of the dial 2|] both for operating the combination, and for changing the combination, by reason of the improvements of the several mechanisms of the lock set forth in detail in said Abbott and Miller U. S. Letters Patent No. 1,956,304. i Within the case I I of the lock 10, tumbler wheels 22, 22, and 22" are journalled on the tube between the base wall l5 and a cam 23, the cam being removably secured upon the extremity of the spindle 16 within the case, as by means of cooperating screw threads on the cam andspindie and a key 24 interposed in keyways formed in the cam and spindle.

The wheel 22 adjacent the cam 23 is driven by a usual pin not shown mounted on the spindle, preferably on the inner face of the cam 23 which is secured as aforesaid on the spindle. The drive from the pin on the cam to the adjacent wheel 22 is by usual means such as a lever journalled on the tube and having one side abutted by the cam drive pin and the other side abutting one end of a segmental flange 0n the wheel 22. Similar drive means carry the drive from the wheel 22 to the wheel 22' and fromthe wheel 22' to the wheel 22". Such drive means are set 6 forth in detail in said Abbott and Miller U. S. Letters Patent No. 1,956,304.

Each of the wheels 22, 22', 22" are preferably of the construction set forth in detail in said Abbott and Miller U. S. Letters Patent No. 1,956,304, and each wheel may be described generally as including a spaced pair of outer ring disc members releasable and engageablewith a hub or center, and the means for effecting the drive from the cam 23 to the wheel 22 and from the wheel 22 to the wheel 22', and from the wheel 22 to the wheel 22" includes the segmental lug or flange on one side of the hub or center, and the pin on the other side of the hub or center of each wheel.

The lock 10 furthermore includes a bolt 35 mounted in suitable ways 36a and 33b formed in the case II, for movement to and from the extended looking or bolting position, illustratedin Fig. 2.

Movement of the bolt 35 to and from looking or bolting position may only be made after the tumbler wheels have been rotated to certain positions relative to each other as determined by the particular combination for which the lock is set. That is to say the combination is determined by the relative location of each wheel center with respect to its outer discs, and the discs of each wheel have outwardly opening registering notches 31 formed therein which must be aligned with the notches of all the other wheel discs for permitting movement of the bolt 35.

The bolt moving means permitted to be operated when the notches 31 of the wheels have been aligned with each other as illustrated in Fig. 1, include an operating lever 38 which is pivotally mounted on the bolt 35 as by means of a pivot screw 39. The lever 38 includes an upper operating arm 38a, extending upwardly from the pivot screw 39 and above the cam 23.

The operating arm 38a has formed thereon a cam follower tongue 381) which extends from the arm 38a towards the axis of the spindle shaft and in line with the cam 23, and the cam 23 has a lever operating notch 23a formed therein which cooperates with the follower tongue 3%- for moving the operating lever and bolt when the: tongue gss permitted to be inserted into the cam notch A spring 39| normally presses the lever arm 38a towards the cam 23, and a stop arm or fence 380 extends from the inside face of the lever arm 38a crosswise of the wheels.

Movement of the lever arm 33a into operable connection with the cam 23 is only possible when the stop arm or fence 330 extends above the aligned notches 31 of the tumbler wheels, and when the cam notch 23a is likewise aligned with the wheel notches 37, at which relative location of the cam notch and wheel notches, the stop arm or fence 38c drops into the aligned wheel notches and the cam follower tongue 38b drops into the cam notch, as shown in Fig. l.

, For the purposes of the present improvements,

as best shown in Figs. 5, 6, and 7, the cam 23 includes a hub 23b and an enlarged cylindrical head 230, the hub 232) having an internally threaded bore 23d and a keyway 236 formed therein for connection with the spindle 15 as above described. The head 230 has a substantial thickness and the cam notch 23a is formed in one end 23] of the head, which is the front end of the head 230 with reference to the door I3 on which the lock I0 is mounted. On the other or rear end 23g of the head 230 there is 7 formed an outwardly opening auxiliary cam notch 23h.

On the upper operating arm 38a of the operating lever 38 there extends a stop pin .40 above the cam 23. A spring dog'arm 4| has its lower end 42 mounted on the side wall 4'3'of the case M, whereby the arm Al is mounted for swinging on the opposite side of the cam 23 from the side wall 44 through which the bolt 35 is mova/bly mounted. The spring dog arm 4| as shown constitutes a formed piece of spring material and includes an upper end 45 which is located for movement to and from blocking and supporting position beneath the stop pin 40 on the operating lever upper arm 38a. Intermediate its ends, the dog arm 4| is provided with an angular cam follower portion 45. The spring pressure of the dog arm 4| urges the dog arm towards the cam 23 so that the apex of the angular cam follower portion 46 is pressed either in the auxiliary cam notch 23h of the cam 23 or against its cylindrical periphery, as shown respectively in Fig. 1, and in Figs. 2 and 4.

In Fig. l, the various parts of the improved combination lock ||l are shown in their relative positions just before the bolt 35 has been fully extended to the locking position, or just after the bolt has been slightly withdrawn from the locking position, with the tumbler wheels having their notches 31 aligned and with the stop arm or fence 38c positioned within the aligned notches and with the cam follower tongue 38?) extending into the operating cam notch 23a. "When from its position as shown in Fig. 1, the bolt 35 is further withdrawn from the locking position by rotation of the dial knob l9 and spindle l6 counterclockwise as viewed in the drawings, the cam follower tongue remains in the cam notch 23a and the bolt 35 is withdrawn to the unlocking position shown in Fig. 4.

When, however, the bolt 35 is fully extended to the locking position as shown in Fig. 2 by clockwise rotation of the spindle I6 from' its position as shown in Fig. 1, during such clockwise rotation the cam notch 23a, after the bolt 35 is fully extended, further causes the cam follower tongue 38b to rise out of the cam notch, elevating the operating lever 38, and the auxiliary cam notch 23h operating on the cam follower portion 46 of the dog arm 4| moves the dog arm 4| to the left from the position shown in Fig. 1 to the position shown in Fig. 2, locating the upper end 45 of the dog arm beneath the stop pin 40 on the upper operating arm 38a. of the operating lever 38 in which position of the operating lever 38 it is supported by the dog arm 4| so that the stop arm or fence 380 is elevated with clearance above the outer peripheries of the tumbler wheels 22, 22, and 22".

Referring to Fig. 1, it is noted that in this position of the lock parts the pin 40 is pressing against the left side of the spring dog arm 4| tending to lower the elevation of the upper end 45 of the spring dog arm. It is also noted that the underside of the pin -0 is curved, and accordingly once the lever 38 has been elevated to clear the notch 23a, and the upper end of the sspring dog arm comes beneath the pin 43 the energy of the spring 6| further elevates the lever 38 so as to raise the lower end of the tongue 38d above the cylindrical surface of the'cam 23. Accordingly, after the tumbler wheels are scrambled from their positions shown in Fig. 2, as is usual after looking a combination lock, since the fence 380 is thus elevated with cleararice above the outer peripheries of the tumbler wheels, there is no way by which an unauthorized person attempting to manipulate the improved combination lock Hi can feel the passage of any tumblernotch 31 beneath the stop arm or fence 380, since there is no contact between either corner of any of the notches of the tumbler wheels with the fence.

When the bolt is in the extended position .and the tumbler wheels are scrambled, both the fence and the tongue 38a are elevated respectively above the tumbler wheels and the cylindrical cam. If at such time the spindle is retated, during each rotation of the spindle, the cam follower portion 48 of the spring dog arm 4| enters the cam notch 23h and the upper end 45 drops below the pin 49, .and the fence 38c drops on the cylindrical surfaces of the tumblers. The lower end of the tongue 38a drops only slightly into the center of notch 23a without contact with either corner of the notch. The angula-rlocation of the notch 23h with respect to the notch 23a, with the spindle axis as a center, is such as to permit dropping of the tongue 38a only into the center of the notch 23a. In the present improved lock ill, the tongue 38a never contacts any portion of the cylindrical cam surface, or either corner of the notch 23a excepting after setting of the combination.

It is to be noted that in the present improved combination lock Ill when the cam follower portion 46 enters the auxiliary cam notch 2371. during rotation of the spindle l6; this movement can be felt by the person turning the dial knob. The fact that this movement can be felt or detected has no relation to the combination setting of the lock, because this action occurs at the same number on the dial 20 with respect to the arrow 2| on the dial ring, irrespective of other combination numbers, and the amount of dial rotation when this occurs is less than that necessary for any part of lever 38 and particularly its fence 38c to contact the tumbler wheels or other parts in such manner that a feel can be detected.

In the present improved combination lock II], the above described changes and modifications of the cam 23, and the combination with the do arm 4| serve to attain the objects of the present invention or discovery with only a very slight increase in the manufacturing costs of the improved combination lock 10 as compared with the lock of the Abbott andlvfiller UFS. Letters Patent No. 1,956,304.

A second embodiment of the improved combination lock of the present invention or discovery is illustrated in Fig. 10 and indicated generally by Ill]. The parts of the lock |||l function substantially the same as the parts of the lock H], and the locks l0 and H0 include identical parts, with the exception that in the lock Hi! the dog arm MI is rigid, and its lower end M2 is pivotally mounted on the bottom wall 41 of the case. The rigid dog arm |4| has an angled formation and includes .a section |4|-| which extends upwardly from the lower end I42 and between the'cam 2 .3 and the case side wall 43 and aligned with the periphery of the cam 23. From the upper end of the section |4|-| there extends laterally substantially at right angles thereto a section |4|2, which is located above the rear portion of the cam 23 and at the rear of the upper operatingarm 38a and beneath the rectangular stop pin 40.

The'section |4|2 of the dog arm |4| terminates with a reversely turned upper end I45 which as shown in Fig. 10 is located beneath the stop pin I40 maintaining the operating lever 38 so that the fence thereon is elevated with clearance above the outer peripheries of the tumbler wheels. The rigid dog arm |4| includes an angular cam follower tongue portion I46 intermediate the ends of the upwardly extending section |4I|. In the cam 23 there is provided an auxiliary cam notch |23h for coacting with the dog arm cam follower tongue I46.

It is noted that in each of the locks H) and III] the axis of swinging or pivoting of each of the dog arms 4| and MI is offset from and parallel with the axis of the spindle IS.

A third embodiment of the improved combination lock of the present invention or discovery is illustrated in Figs. 11, 12, and 13 and indicated generally by 2|0. The parts of the lock 2 Ill function substantially the same as the parts of the locks I and H0, and the locks II), III], and 2|0 include identical parts, with the exception that in the lock 2|0 the rigid dog arm 24| has a lower end 242 which is pivotally mounted on the bottom wall 4! for pivoting about an axis below and at right angles to the axis of the spindle IE. The dog arm 24| is located between the inner end of the cam 23 and the cover 48 of the case.

The upper end 245 of the dog arm 24I swings towards and away from the cam 23 and to, and from a position in which it is located beneath the stop pin 24!] as shown in'Figs. 11 and 12 maintaining the operating lever 38 so that the fence thereon is elevated withclearance above the outer peripheries of the tumbler wheels. The dog arm 24I includes a lateral extension 24I-3 which is connected by a tension spring 49 with the case front wall I5. Swinging movement of the dog arm 24| is effected by means of a cam boss 50 located on the rear face of the cam 23 and which operates against a cam follower head located on the opposite face of the dog arm 24I. When the fence of the lock 2I0 is ready to drop into the tumbler Wheel notches as shown in Fig. 13, the auxiliary cam boss 50has ridden across the cam follower head 5| and swung the dog arm 24I to the position shown in Fig. 13 out of blocking position with respect to the stop pin 240. i

The spring dog arm 4| may be otherwise stated to be internally spring pressed by reason of the spring material of which it is constituted and its particular formation thereof. Each of the dog arms MI and MI may be otherwise stated to be externally spring pressed, by their above described construction and arrangement. Thus, each of the dog arms 4|, MI, and 24| may be broadly termed to be a spring pressed dog arm.

It is noted that the dog arm |4| has a sloping extremity for its reversely turned upper end 5. Likewise, it is noted that the dog arm 24| has a'sloping extremity for its upper end. Each of these sloping extremities coact respectively with the pins I40 and 240 during an upward movement of the associated lever 38, whereby the fence on the leveris given the desired elevation.

In the foregoing description, certain terms have been used for brevity, clearness, and understanding, but no unnecessary limitations are to be implied .therefrom beyond the requirements of the prior art, because suchwords are used for descriptive purposes herein and are intended to be broadly' construed.

Moreover, the embodiments of the improved construction illustrated and described herein are by way of example, and the scope of the present invention is not limited to the exact details of construction.

Having now described the invention or discovery, the construction, the operation, and use of preferred embodiments thereof, and the advantageous new and useful results obtained thereby; the new and useful constructions, and reasonable mechanical equivalents thereof obvious to those skilled in the art, are set forth in the appended claims.

We claim:

1. In combination lock construction including walls forming a case and including a base wall, a tube extending from the base wall, a spindle journalled in the tube, one or more tumbler wheels journalled on the tube, a dial knob on the spindle beyond the case, a cam on the spindle within the case and beyond the tumbler wheels, the tumbler wheels each being formed with an outwardly opening notch, the cam being formed with an operating notch, drive means operative between the cam and the adjacent tumbler wheel and drive means operative between each adjacent pair of tumbler wheels, a bolt mounted in the case for movement to and from an extended locking position, an operating lever, a pivotal connection between the operating lever and the bolt, the operating lever including an upper arm extending above the spindle and having a cam follower tongue depending towards the cam, a fence extending from the upper operating lever arm parallel with the axis of the spindle, the cam notch and the tumbler wheel notches being arranged for alignment with each other by setting of the combination and for reception of the fence in the aligned cam notches and the cam follower tongue in the cam notch when the combination is set, for withdrawing and extending the bolt from and to the locking position; the

combination including a stop member on the operating lever arm adjacent the cam, dog means mounted for swinging on the case, the dog means including a cam follower portion, means urging the cam follower portion of the dog means against the cam, and the lever arm having an upward movement positioning the stop member so that the dog means is in a position beneath and supporting the stop member and the operating lever and maintaining the fence with clearance above the tumbler wheels when the bolt is in the fully extended locking position, and the cam being formed with an auxiliary cam notch receiving the cam follower portion of the dog means and displacing the dog means from beneath the stop member when the cam notch is below the tongue.

2. In combination lock construction including walls forming a case and including a base wall, a tube extending from the base wall, a spindle journalled in the tube, one or more tumbler wheels journalled on the tube, a dial knob on the spindle beyond the case, a cam on the spindle within the case and beyond the tumbler wheels, the tumbler wheels each being formed with an outwardly opening notch, the cam being formed with an operating notch, drive means operative between the cam and the adjacent tumbler wheel and drive means operative between each adjacent pair of tumbler wheels, a bolt mounted in the case for movement to and from an extended locking position, an operating lever, a pivotal connection between the operating lever andthe 11 bolt, the operating lever including an upper arm extending above the spindle and having a cam follower tongue depending towards the cam, afence extending from the upper operating lever arm parallel with the axis of the spindle, the cam notch and the tumbler wheel notches being arranged for alignment with each other by setting of the combination and for reception of the fence in the aligned cam notches and the cam follower tongue in the cam notch when the com-' bination is set, for withdrawing and extending the bolt from and to the locking position; the combination including a stop pin extending from the upper operating lever arm above the cam, spring pressed dog means mounted for swinging on the case, the dog means including a cam follower portion, the cam follower portion being urged against the cam by the spring pressure and the lever arm having an upward movement positioning the stop member so that the dog means is in a position beneath and supporting the stop pin and the operating lever and maintaining the fence with clearance above the tumbler wheels when the bolt is in the fully extended locking position, and the cam being formed with an auxiliary earn notch receiving the cam follower portion of the dog means and displacing the dog means from beneath the stop pin when the cam notch is below the tongue.

3. In combination lock construction including walls forming a case and including a base wall, a tube extending from the base wall, a spindle journalled in the tube, one or more tumbler wheels journalled on the tube, a dial knob on the spindle beyond the case, a cam on the spindle within the case and beyond the tumbler wheels, the tumbler wheels each being formed with an outwardly opening notch, the cam being formed with an operating notch, drive means operative between the cam and the adjacent tumbler wheel and drive means operative between each adjacent pair of tumbler wheels, a bolt mounted in the case for movement to and from an extended locking position, an operating lever, a pivotal connection between the operating lever and the bolt, the operating lever including an upper arm extending above the spindle and having a cam follower tongue depending towards the earn, a fence extending from the upper operating lever arm parallel with the axis of the spindle, the cam notch and the tumbler wheel notches being arranged for alignment with each other by setting of the combination and for reception of the fence in the aligned cam notches and the cam follower tongue in the cam notch when the combination is set, for withdrawing and extending the bolt from and to the locking position; the combination including a stop pin extending from the upper operating lever arm above the cam, a spring pressed dog arm mounted for swinging on the case, the dog arm including a cam follower portion intermediate its ends and an upper end adapted for movement by ooaction of the cam with the cam follower portion of the dog arm, the upper end of the dog arm being in a position, and the cam being formed with an auxiliary cam notch receiving the cam follower portion of the dog arm and displacing the upper end of the dog arm from beneath the stop pin when the cam notch is below the tongue.

A. In combination lock construction including 12 wells; forming a case and including abas wall, a tube extending from the base wall, a spindle journalled in the tube, one or more tumbler wheels journalled on the tube, a dial knob on the spindle beyond the case, a cam on the spindle within the case and beyond the tumbler wheels, the tumbler wheels each being formed with an outwardly opening notch, the cam being formed with an operating notch, drive mean 'operative between the cam and the adjacent tumbler wheel and drive means operative between each adjacent pair of tumbler wheels, a bolt mounted in the case for movement to and from an extended locking position, an operating lever, a pivotal connection between the operating lever and the bolt, the operating lever including an upper arm extending above the spindle and having a cam follower tongue depending towards the cam, a fence extending from the upper operating lever arm parallel with the axis of the spindle,the cam notch and the tumbler wheel notches being arranged for alignment with each other by setting of the combination and for reception of the fence in the aligned cam notches and the cam follower tongue in the cam notch when the combination is set, for withdrawing and extending the bolt from and to the locking position; the combination including a stop pin extending from the upper operating lever arm above the cam, a dog arm of formed spring material, means mounting the dog arm for swinging on the case, the dog arm including a cam follower portion formed intermediate its ends and an upper end adapted for movement by coaction of the cam with the cam follower portion of the dog arm, the upper end of the dog arm being in a position beneath and supporting the stop pin and the operating lever and maintaining the fence with clearance above the tumbler wheels when the bolt is in the fully extended locking position, and the cam being formed with an auxiliary cam notch receiving the cam follower portion Ofthe dog arm and displacing the upper end of the dog arm from beneath the stop pin when the cam notch is below the tongue.

5. In combination lock construction including walls forming a case and including a base wall, a tube extending from the base wall, a spindle journalled in the tube, one or more tumbler Wheels journalled on the tube, a dial knob on the spindle beyond the case, av cam on the spindle within the case and beyond the tumbler wheels, the tumbler wheels each being formed with an outwardly opening notch, the cam being formed with an operating notch, drive means operative between the cam and the adjacent tumbler Wheel and drive means operative between each adjacent pair of tumbler Wheels, a bolt mounted inth'e case for movement to and from an extended looking position, an oper'atih'g lever, a pivotal connection between the operating lever and the bolt, the operating lever including an upper arm extending above the spindle and havin a cam follower tongue depending towards the cam, a fence extending from the 'upper operating lever arm parallel with the axis of the spindle, the camnotch and the tumbler wheel notches being arranged for alignment with each other by setting of the combination and for reception of the fence in the aligned cam notches and the cam follower tongue in the cam notch when the combination s set, for withdrawing and extending the bolt from and to the locking position; the combination including a stop member on the operating lever arm adjacent the cam, dog means mounted for swinging on the case, the dog means including a cam follower portion, means urging the cam follower portion of the dog means against the cam, and. the lever arm having an upward movement positioning the stop member so that the dog means is in a position beneath and supporting. the stop member and the operating lever and: maintaining the fence with clearance above the tumbler wheels when the bolt is in the fully extended locking position, and the cam being formed with an auxiliary cam coacting with the cam I014 lower portion of the dog means and displacing the dog means from beneath the stop member when the cam notch is below the tongue.

HERBERT C. BEHRENS. ALBERT L. ABBOTT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

